What do you mean? A limit to the number of forks? There is an infinite number of forks possible, and also it could fork of a fork if the fork developers felt that is where they want to break from. E.g. a fork does not have to happen on the main bitcoin core chain, it could just as easily happen off the BitcoinCash chain. It all depends on where the developers of the new fork believe they improve things or can gain an advantage. Ultimately it depends on what they are trying to achieve.